Which branch of the autonomic nervous system is activated during the 'fight or flight' response, leading to increased heart rate and blood pressure?

The branch of the autonomic nervous system activated during the 'fight or flight' response is the sympathetic nervous system. The autonomic nervous system is the part of the nervous system that controls involuntary bodily functions, such as heart rate, digestion, and breathing. It has two main divisions: the sympathetic and parasympathetic nervous systems. The sympathetic nervous system is specifically responsible for initiating the 'fight or....